Traijst control



' JNVENTQR. fi G? flav BY M TTORNEY H. P. OBER TRAIN CONTROL Filed Aug. 15, 1924 Patented Aug. 21, 1928.

UNITED STATES HERMON P. OBER, OF ROCHESTER, NEX YORK, i

SHE-1910B TO GENERAL RAILWAY SIGNAL COMPATTY, OF l-U\1.fi..4.. .423, NEW YORK.

TRAIN CONTROL.

Application filed August 15. 1924.

This invention relates to automatic train control systems 01 the continuous inductive type.

In the application of automatic train control to railway systems, points are encountered at which branch. linciJ, sidings or other trackway sections unequipped for train control operation leave a section of the main line trackway which is so equipl ed. When a train equipped for automatic train control operation passes over the track switch and into such unequipped territory, the car-carried appa 'atus on the train will act on the brakes in such a manner that the train will be unable to proceed at all. or Will be able to proceed at a restricted speed only, depending upon the type of train control system employed. In order to prevent this diiiiculty, it proposed in accordance with the presentinvention to provide means making it possible for the engineer or train operator to render the car-carried brake control apparatus inact-ive while the train is located on the main traclzway and before passing over the switch to the unequippe'd branch or siding.

In order that the engineer or train operator may not render the car-carried automatic brake control apparatus inactive while proceeding on the main line t-rackway whichis equipped for automatic train control, it is also proposed in accordance with the present invention to control the means for r adoring the car-carried automatic brake control apparatus inactive in accordance with the position of the track switch leading to the unequipped branch trackway. so that the enginccr may render the brake control apparatus inactive only it said switch is set for a turnout move into said branch trackway.

In automatic train control systems of the continuous inductive type control influences corresponding; to trafiic conditions ahead are usually transmitted to a moving vehicle by ri :ans oi? currents flowing in the track rails. It sometii'nes desirable to employ a current which flows in the two track rails in multiple. in which case balance resistances or equivalent means are required to connect control wires to the track rails at each end of a blocl: for applying); such current. In order to reduce the number of such balance resistances or equiva lent means required. for a given section of tracltway. and in o 'der to cut down the amount of current used to provide automatic Serial No. 732 212.

train control, it is further proposed in accordance with the present invention to provide means whereby the control current may flow in a path comprising the wheels and axles of the vehicle one track rail behind the *ehicle and the two track rails in multiple in front of the vehicle.

Other objects and advantages of the invention will be pointed out or will be apparent as the description progresses. In the drawings. a section oft tracltway equipped with features embodying the present invention together with a diagrammatic showing oi sim plitied and typical car-carried apparatus for use theewith nave been shown.

Any suitable train control system in which car-carried apparatus is continuously influenced by a control current flowing in the track rails may be used with the present invention. The particular system chosen for the purpose of illustrating the nature of the invention is of the type which acts to cause a restrictive brake application whenever the train enters a caution block or a danger block.

lletcrring particularly to the trackway apparatus shown, the track rails l are divided into blocks in the usual way by the insulating .joints 2. the block I and the adjacent ends of two other blocks H and J having been shown. In order to simplify the explanation, the similar devices shown in the several blocks have been assumed to be the same and have been referred to by like reference characters having distinctive exponents.

The particular type of traclnvay equipn'ient shown employs two cotrol currents flowing in the track rails. One current, termed the loop or track phase current. flows in the two tracl: rails in series; and the other current, ermed the simplex or line phase current. flows in the two track rails in multiple. The track phase current is impressed on the track rails 1. a i the eritend oi each block by means on". the transformer 3, the primary winding of which is energized from the transmission line s as shown. An inductive reactance 5 is included in the track phase circuit for reasons which will. be hereinafter explained. The track phase circuit is completed at the entrance end of the block through the usual track relay 6 having movable contact fingers 7 and 8. The line phase currentis applied to the two track rails in multiple by two connections, one at the exit end of each block through the balance resistance 9 and the other to one rail at the entrance end of the block, this circuit including the secondary of the transformer 10, whose primary winding is connected across the transmission line 1 as shown.

Referring now more particularly to the switch protection arrangement, which in part constitutes the present invention, a track switch of the type common in railway practi: c has been conventionally re iresented at S in the block I. This track switch S may be manually or power o ierated, and may be controlled locally or from some remote point. The details of construction or? the track S and its operating mechanism have not been shown, as the construction of track switches is well known to those skilled in the art and as the particular construction. used forms no part of the present invention. he track switch leads to a sidine; or branch line K, which is assumed to be uncquipped for train control ope ation. A switch box has been conrcntionally represented at SW, carrying the switch box contact lingers 11, 12, 13, let and 15. These switch box contact fingers are mounted on and insulated from a suitable base, and are operated in accordance with the position oi the track switch S by a rod 16 which is secured to a moving part of the tr ck switch S, and is pivotally connected to the switch box contact lingers 1115 and insu lated therefrom shown. The switch box contact lingers operate to make and break circuits which will be hereinafter described.

A railway vehicle has been conventionally represented in the block H by the wheels and axles 17, the normal direction of tavel of such vehicle being indicated by the arrow. In front oi? the leading and behind the trailine' axles of the vehicle, over and in inductive relation to the track rails 1, are mounted two sets of receiving coils 18 and 19 which may or may not have laminated iron cores. The coils 18 in front are so connected that voltages induced therein by track phase current flowingin the two trek. rails in series are additive, while the coils 19 in the rear are so connected that voltages induced therein by the line phase currents flowing; in the two track rails in multiple are additive.

Any suitable type of car-carried control apparatus adapted to apply the brakes or otherwise restrict the progress ot the train may be employed. In the simplified type chosen for the purpose of illustration, a polyphase main car relay MB of the three-posh tion type well known in train control prac tice and having two field .vindin sQO and 21 is used. The field windings 20 and 21 are energized from the amplifiers 22 and 23, which are connected with the receiving coils 19 and 18, respectively, through circuits which resonated by the condensers 2atand 25. The main car relay MR has a moving element or rotor 26, constructed to operate the contact fingers 27 and 28 to any one of three difi'erent positions, as conventionally shown in the drawings. A non-control push button NB is provided, being preferably located within easy access of the engineer, and operates two contact fingers 29 and 80. A noncontrol relay N C is electrically associated with the push button NB, this relay preterably having its elements so proportioned and arranged that it is slow acting, that is, its contact fingers 31 and 32 do not move to close or open their stationary contacts until an appreciable predetermined period oi time after the energization or de-eiierg'ization ot' the relay windings.

Brake control apparatus of any suitable type may be employed. This apparatus 11 ay act to apply the brakes and bring" the vehicle to a stop under dangerous trallic conditions ahead, may impose more restrictive speed limits the train proceeds in a caution block, or it may act in any other suitable manner to limitthe progress of the train. For the sake of simplicity, this brake control apparatus has been diaerannnatically illustrated by the device BA which is assumed to initiate a re st ictive braking operation upon de-energization oi a circuit through this device.

0pm'a/ i0n .Before describing the operation of the switch and sidingprotecting equipment, embodying the present invention, the operation of the simplified control apparatus shown will be explained; All controls and devices have been shown in their normal positions, that is, the positions assumed with a train proceeding under clear traffic conditions and with all closed circuit-s properly energized. Track phase current will be flowing in the track rails through a circuit which is obvious from the drawings. When a train enters a given block, say the block I, the line phase current will flow through a circuit which may be traced as followsz-itrom the secondary of the transformer 10, through wire 3?), contact finger 7 and front contact of the track relay 6 wire 34, balance resistance 5), through the two track rails 1 in multiple to the point at which the train under consideration is located, joining through the wheels and axles of the vehicle and flowing through one track rail and the wires 35 and 36, contact linger 8 and back contact of the track relay 6 which will be de-energized due to the presence of a train in the block] shunting the track phase current from this track relayti and thence through wire 3. ,switch box conla 'nger 15 and its stationary contact 38 and wire 39 to the secondary of transformer 10. It will be seen from the circuit traced above that no line phase current-will flow in the track rails until a train enters a given block because the line phase circuit is broken at the cent ct finger Set the track relay 6 when the block unoccupied. Thiseiiect-s a saving; in

the power consumed by the trackway apparatus.

The track and line phase currents are dis-- placed in phase because of the inductive reactance located in the track phase circuit. Currents induced in the receiving coils 18 and 19 by the track and line phase currents respectively are amplified and impressed on the windings 20 and. 21 of the main relay MR. As there is a phase displacement between the currents in the two field windings, a torque is produced in the rotor 26, and this rotor with its associated contact fingers 27 and 28 is swung into one extreme position as shown. The contact finger 27 engages its stationary contact, completing an energizing circuit to the brake control apparatus BA, and maintaining said apparatus inactive and allowing the train to proceed at speed.

Now assume. that the train under consideration enters a block in which danger or caution trafiic conditions exist, that is, a block in which tl track or line phase currents are not flowing in the track rails by reason of a train, a broken rail or other hazard in the block under consideration or in the next block in advance. One of the windings 20 and 21 of the main relay'MR will not receive current, and therefore no torque is produced in the rotor 26, whereupon this rotor with its associated contact fingers 27 and 28 assumes its neutral position. The contact finger 27 disengages its stationary contact and so deenergizes the brake control apparatus. BA,

=' causing" a brake application or a speed restric tion depending, on the type employed.

Referring now more particularly to the operation of the switch protecting apparatus embodying the present invention, if a train enters the block I in which the track switch S is located and this switch is closed, that is, set for train travel. on the main line track, the train under consideration may proceed in the block I without restriction. If, however, it is desired to make a turn-out move onto the siding or branch line K, the engineer will bring the train to a stop with the locomotive or other vehicle equipped for train control on the section of the track rails between the points 40 and 41. The brakeman or other operator will then set the switch S to the position for a turn-out move, and the switch box contact fingers 1115 being operated by the position of the switch S, will assume the positions indicated by the dotted lines. An excess amount of line phase control current will now flow in the track rails between points 40 and 41 through a circuit which may be traced as follows: from the secondary of the transformer 42, the primary of which is energized from the transmission line 4 as shown, through wires 43 and 44, dividing through balance resistance 45, passing in multiple through wires 46 and 47, stationary contacts and contact fingers 11 and 12 and wires 48 and 49 to the track rails at the point 41, through the two track rails in multiple to the point 40, wires 50 and 51, uniting at the contact finger 13 and its stationary contact, and through wire 52 to the secondary of the transformer 42. The transformer 42 is designed to supply the circuit just traced wi h an amount of energy which is in excess of the amount ordinarily supplied to the track rails for control purposes.

The engineer will now depress the non-c0ntrol push button NB, closing the front contact of the finger 29 of the push button and opening the back contact of the finger 30. lVhen the back contact of the finger 30 is opened, a resistance 53 is inserted into themput circuit from the receiving coils 19, which resistance would ordinarily so reduce the amount of energy supplied to the amplifier 22 as to cause the deenergization of the main. relay Mli. but as there is '1 excess amount of line phase current supplied to these coils at this point, the main relay MR remains energized.

The closingof the back contact of finger 29 of the. push button NB with the main relay energized causes the energization of the noncontrol relay NC through a circuit which may be traced as follows :-from the battery terminal B, through contact finger 28 and stationary contac 54 of the main relay MR, wire 55, contact finger 29 and its front contact, wires 56 and 51'' and the winr of the non control relay NC to the battery terminal C. The energization of the non-control relay NC causes attraction of its contact fingers 31 and closing their front contacts. The closing of the front contact of finger 31 has no inimediate effect. The closing of the front contact of finger 32 completes a circuit to the brake control. apparatus BA which circuit is obvious from the. drawings. the vehicle passes the point 41 and enters the branch line or siding K, the receivingcoils 18 and 19 fail to receive current and the main relay MR is deenerggized. It is necessary that the eng neer maintain the push button NB depressed until. the de-energization of the main relay ME. The de-energization of the main relay MR causes its contact fingers 28 to engage the stationary contact 58, completing the stick circuit for the non-control relay NC which may be traced as follows :from the battery terminal 13, through contact finger 28 and stationary contact 58 of the main relay MR, wire 59, contact finger and front contact 31 of the non-control relay NC, wires (30 and 57 and the winding of the non-control relay NC to the battery tern'iinal C. \Vhen this stick circuit to the non-control relay is completed, the en- 'ineer may release the push button NB.

With the non-eontrol relay NC ener r d through the stick circuit iusttraced, the brake control a 'iparatus BA. is enero'ized through a circuit including the contact linger 32 of the track rails between the entrance end ot aand the track switch S. lVhen the track switch S is set for a turn-out move, the line phase current is applied to the track rails between the track switch S and the exit oi? the block only, and flowing in a circuit which may be traced as iollows:-i'ron1 the secondary winding 01" the transformer 10, through wire 33, contact iinger 7 and front contact of track relay wire 3 balance resistance 9, divided and lowing in multiple through the two tracl; rails 1 to the point 41, through wires 48 and 49, switch box contact fingers 11 and 12 and their associated stationary contacts, wires to and a7, uniting through balance'resistance 45, wires M and ()1, switch box contact finger l t, stationary contact G t, wires (35 and 39 to the secondary oi the transiormer 10.

t is seen from the circuit traced above that when the track switch S is set for a turnout move, no line phase current flows in the track rails between the entrance end of the block and the track switch, making this portion oi. the block a danger section, and sorestricting the progress of a train entering such section under these conditions. It is also clear that both track and line phase currents are present in the track rails between the point 41 and. the eXit end of the block, so that a train proceeding in this section will not be restricted by the operation of the track switch block S. When the track switch S is open, it should be noted that the track rails are shunted at the point 40 by the wires and 51 and the switch box contact finger 13. For this reason, no track phase current will How in the track rails between the point 40 and the entrance end of the block.

It is to be understood that the system shown and described has been disclosed for the purpose oi illustrating the nature of the invention ra her than for the purpose of indicating its scope. It clear that many modifications or additions to the system shown could be made'with out departing from the spirit of the present invention. For instance, means for reversing the connections to the receiving coils 18 and 19 so that the vehicle may proceed with either end leading might be included, cab signals or indications might be used or many other modifications, additions or combinations might be resorted to, without departing from the ini'eifition or the idea oi means underlying the same.-

\Vhat itis desired to secure by Letters Patent is 1. In an automatic train control system, the

menses combination with car-carried apparatus including a brake control device, and means carried apparatus only when the track switch is in a given position.

2. In an automatic train control system, the combination with vehicle carried apparatus including brake control means and means for controlling said brake control means in response to control energy transmitted to said vehicle carried apparatus from the t rackway, manually controllable means for rendering said brake control means inactive only ii an amount of energy in excess of said control energy is received from the trackway and track'way apparatus including a track switch, and-means controlled by the operation of said track switch to transmit said excess amount of energy to said vehicle carried apparatus only when said track switch is in a given position, whereby saidbrake control means maybe rendered inactive when the vehicle is to proceed over a given branch of trackway.

3. In an automatic train control system for railways having a main line trackway equipped for automatic train control and a section of trackway not so equipped and con nected to said main line trackway by a track switch, the combination of vehicle carried train speed control apparatus, normally controlled in response to energy transmitted from the trackway, and manually controllable means for rendering said apparatus inactive in response to an amount of energy in excess of said control energy transmitted from the trackway, means governed in accordance with the position of said track switch for transmitting said excess amount of energy from said main linetrackway to said vehicle carried apparatus when the track switch is set to allow the vehicle to proceed into said unequipped section of traclm'ay.

i. In an automatic train control system, in combination with vehicle carried apparatus including means for applying the brakes of the vehicle in response to the cessation of control energy normally received from the trackway, and means for rendering said brake applying meansinactive in response to an excess amount of energy received from the traclrway, a section of trackway provided with a track switch, and means governed by the position of said track switch and acting to cut off said control energy in the portion of said section of trackway in the rear of iii) i,cs1,903

said track switch, and to set up said excess amount of energy in a portion of the trackway adjacent the track switch when said track switch is in a given position.

5. In an automatic train control system of the type in which control influences corresponding to traffic conditions ahead are con tinuously transmitted from the trackway to a moving vehicle, vehicle carried apparatus including means for controlling the brakes of the vehicle in accordance with control energy received from the traekway. and manually controllable means for rendering said brake control apparatus inactive only in response to an amount of energy in excess of said control energy transmitted from the trackway, a section of the trackway provided with a track switch leading to a branch of the trackway which is unequipped for automatic train control, and means controlled by the position of said track switch for transmitting said excess amount of energy to the track rails adjacent said track switch when said track switch is in the position for train travel on said uneqnipped branch trackway, whereby the brake controlling means may be rendered inactive when a train enters said unequipped branch trackway.

6. In an automatic train control system of the type in which control influences are continuously transmitted to a moving vehicle by electric currents flowing in the track rails, a circuit for said currents in an insulated section of the track rails comprising a source of energy connected through a balancing re sistance to the two track rails at one end of said section, and to one track rail only at the other end of said section.

7. In an automatic train control system, car-carried brake control apparatus controlled by influences received from the trackway, means for supplying an electric current to set up said influences in an insulated section of the trackway comprising a balancing resistance for impressing a current on the two track rails in multiple at one end of said section, a line wire for returning said current from one track rail only at the other end of said section to said balancing resistance, and means for cont-rolling the current flowing in said line wire in accordance with traffic conditions.

8. In an automatic train control system, a circuit for carrying a control current in an insulated section of trackway comprising a source of current, a balancing resistance for impressing such current upon the track rails in multiple at one end of said section, a line wire for returning said current from one track rail only at the other end of said section to said source of current, and means for closing the circuit through said line wire only when a vehicle is located in said section.

9. In an automatic train control system, a section of trackwa-y having a track switch therein, a circuit for a control current in said section comprising a line wire connected through a balancing resistance to the two track rails in multiple at one end of said section and to one track rail at the other end 0i said section, the circuit through said line wire including a source of electrical energy, circuit closing means closed only when a. vehicle is in said section, and a second circuit closing means controlled by the position of said track switch.

10. In an automatic train control system, iLI'-C1ll"l0(l brake control apparatus controlled by influences received from the track way, means for supplying an electric current to set up said influences in an insulated section of the trackway comprising a balancing resistance for impressing a current on the two track rails in multiple at one end of said sec tion, a. line wire for returning said current from one track rail only at the other end of said section to said balancing resistance, and means for interrupting current flow in said line wire under clear conditions in said section.

11. In an automatic train control system, the combination with car-carried apparatus i eluding a brake control device, and means for controlling said device in response to control energy transmitted from the trackway, of manually controllable means including a retarded action device for rendering said brake control device inactive only if an amount of energy in excess of said control energy is received from the trackway, a track switch, and trackway means adjacent said track switch for transmitting said excess amount of energy to said car-carried apparatus only when the track switch is in a given position.

12. In an automatic train control system, the combination with car-carried apparatus including a brake control device, and means for controlling said device in response to con t-rol energy transn'iitted from the track 'ay, of manually controllable means including a retarded action stick relay for rendering said brake control device inactive only if an amount of energy in excess of said control energy is received from the trackway, a track switch, and trackway means adjacent said track switch for transn'iitting said excess amount of energy to said car-carried apparatus only when the track switch is in a given position.

13. In an automatic train control system, the combination with car-carried apparatus including a brake control device, and means for controlling said device in response to control energy transmitted from the trackway, of manually controllable means including a retarded action stick relay, controlling an auxiliary energizing circuit for said brake control device and having a stick circuit controlled by the first mentioned means, for rendering said brake control device inactive only it an amount of energy in excess of said control energy is received from the trackway, a track switch, and. traclcway means adjacent said track switch for transmitting said excess amount of energy to said car-carried apparatus only when the track switch is in a given position.

14-. In an automatic train control sys'tei'n, the combination with car-carried apparatus including: a brake control device, and means for controlling aid device in response to ontrol energy transmitted from the trackway, of manually controllable means including a retarded action stick relay, controlling an auxiliary energizing circuit for vsaid brake control device and having a stick circuit controlled bytlgic first mentioned means, for rendering said brake control device inactive only it an amount of energy in excess of said control energy is received from the trac-kwa y, a track switch, and track-Way ncans adjacent said track switch for transmitting said excess an'ioun-t 01 energy tosaid car-carried apparatus only when the track switch is in a. given position and a pick-up circuit for the stick rel controlled by said norn'ialjly controllable means.

In testimony whereof I ailix my signature.

HERMON P. OBER. 

